What's Hot: Large solar panels, intelligent solar charging, comes with full set of cables and a DC adapter.

What's Not: It could still take many hours to charge the battery if you don't have full sun.

We all would like to live a greener life, Revolve Electronics makes it easier for us to do our part by offering external batteries with solar charging options. The hybrid batteries come in two capacities: the xeMilo has 4,400 mAh capacity and the xeMini Plus has 2,200 mAh. Both come with large solar charging panels and can power two devices simultaneously. The xeMini Plus we used for this review is small and easy to carry on the road, and can charge any device with an USB charging port and requires 5V DC and 1.2a max or lower to charge.

Design

The Revolve xeMini Plus battery pack really comes in two parts: one is a Lithium Polymer battery that can store 2,200mAh battery power, and the other is a wood-plastic composite casing that houses the solar panels and charging ports. The Revolve xeMini Plus Battery Pack has ?green? features inside and out. The rechargeable battery sits in the battery pack just like the one sitting in most the cell phones: you can take it out when it?s time to replace it without discarding the rest of the pack especially the expensive solar panels. The battery casing itself is made with recycled and bi-products including bamboo sawdust waste and recycled automotive plastic. The composite material is very sturdy, won?t crack easily and will last you for years to come.

Like with all Revolve batteries, the xeMini Plus has a built-in wall AC adapter that?s designed to conveniently take the lower charging slot and share the outlets with other power adapters. The Revolve xeMini Plus Battery has two charging ports, one passes through power and the other passes power as well as data so that you can sync one device while it?s plugged into the battery. The Revolve xeMini Plus also has a mini-USB input port, and you can charge the battery via computer, vehicle DC and AC outlet using the included cable and DC adapter. The battery has a button for you to check the power level, and two front LED lights indicating charging status.

The Revolve xeMini Plus Battery Pack measures 3.5 x 4.123 x 0.69 inches and weighs 6.2 oz. It?s small enough for you to toss it in any gear bag to take on the road.

Features

We?ve looked several solar-powered battery packs, to be honest, some succeed and many fail. The main issues for the solar-powered battery packs as a category include long charging time and high requirement for sun exposure. The Revolve xeMini Plus Battery Pack is among the best solar-charging solutions we?ve seen. The solar panels on the front are large enough for serious light energy charging, and the battery has Revolve?s Light Assisted Power behind the glass encapsulated cells. According to Revolve, the photovoltaic silicon panels used in the Revolve xeMini Plus have very high efficiency, and the glass cells also last longer. But the biggest benefit the Light Assisted Power technology provides is that it doesn?t require full sun to charge the battery pack efficiently. Even on a cloudy day, the battery can still trickle charge thanks to the high efficiency cells and the unique solar charging technology. Luckily we tested the battery pack in the hot Texas summer sun, and it charged fully in just a few hours. If you don?t get full sun, the battery could take as much as 13 hours to charge fully.

You can also charge the Revolve xeMini Plus Battery Pack via an AC outlet (100-240V) or USB DC 5V, 2A. The Revolve xeMini Plus Battery Pack comes with three USB cables: an USB mini cable for charging the battery pack, an USB micro cable for charging your mobile devices with microUSB port, an USB male to female cable. The included vehicle 12V DC adapter fits vehicle power socket or cigarette lighter and it has an LED light to let you know if power is coming through. Charging the Revolve xeMini Plus Battery Pack via computer takes about 3-4 hours, and faster via AC. The DC charger has rapid charging technology built in, and it takes a few hours to fully charge the battery.

How about charging device using the Revolve xeMini Plus Battery Pack? The 2,200mAh comes in very handy when you are traveling and away from a power outlet all day. The add benefit of this battery pack is the solar charging option that allows the battery pack to continue absorbing power all day as long as you have some light in the room. It fully charges the iPhone 4 in 1.5 hours. Of the two USB charging ports on the Revolve xeMini Plus Battery Pack, one of them is also a sync port. So when you connect the battery to your computer, you can sync your iPhone 4 while both the battery and the iPhone 4 are charging.

The built-in Lithium Polymer battery lives under a battery door on the back. It has at least 500 full charge cycles, and when the cycles run out you can get a replacement battery and can still use the charger. And since it use USB ports to power devices, any mobile device that works with an USB port can work with the Revolve xeMini Plus Battery Pack, including mobile phones, MP3 players, digital cameras, handheld gaming systems, and more. However the battery outputs 5V 1.2 amps max, so large devices like tablets that require 2A or more will not work with the Revolve xeMini Plus Battery Pack. For tablets like the iPad 2, Galaxy Tab or BlackBerry PlayBook or ebook readers like the Kindle, check out the xeMilo that outputs 5V 2.8A max power.

Conclusion

It?s a win-win situation when you can power your mobile devices with solar power and carry the battery with you on the road. The Revolve xeMini Plus Battery Pack proves to be a viable solution even when you don?t live or travel to places with full sun all day thanks to the intelligent solar charging technologies. The battery is small and light enough for the road, and it can continue to charge while sitting in your car or on a windowsill. It comes in both 2,200mAh and 4,400mAh versions depending on what devices you need charging. The battery pack can also sync your data while charging. All in all this is a very nice solution as portable power for those who want to live a green life!